Examine this content from /etc/chrony.conf: ... pool pool.ntp.org offline driftfile /var/lib/chrony/drift keyfile /etc/chrony.keys ... Which statement is true about pool.ntp.org?

The offline option specified for the pool pool.ntp.org directive in the /etc/chrony.conf file instructs the chronyd daemon to not poll this source upon startup. The source is considered to be unavailable by default. For chronyd to start using this pool for time synchronization, an administrator must manually enable it. This is accomplished by using the online command within the chronyc command-line interface, which is the user-facing tool for monitoring and controlling the chronyd daemon. This feature is particularly useful for intermittent network connections where polling should only occur when the connection is known to be active.

A. The number of sources used from a pool is controlled by the maxsources option, which defaults to 4, not 3. This is unrelated to the offline directive's function.
B. The chronyd daemon itself does not enable the source; it requires explicit user intervention via the chronyc utility to bring the source online.
C. This describes the behavior of the autooffline option, which automatically marks a source as offline after a series of failed polls, not the offline option.

1. chrony.conf(5) Manual Page: The official man page for chrony.conf describes the offline option for server/pool directives. It states, "The offline option tells chronyd to not try to poll the source until it is enabled by the user with the online command of chronyc." (Accessed via man 5 chrony.conf on a standard Linux system).

2. chronyc(1) Manual Page: The man page for the chronyc utility details the online command. It specifies, "The online command is used to tell chronyd that a source which was previously declared to be offline (using the offline option in the configuration file, or the offline command in chronyc) is now online." (Accessed via man 1 chronyc).

3. Oracle® Linux 8 Documentation: In the "Configuring Basic System Settings" guide, Chapter 10, "Configuring NTP Using the chrony Suite," the documentation explains the use of chrony.conf options. Section 10.3.1, "Understanding the /etc/chrony.conf File," details how directives and their options, including offline, control the behavior of the chronyd daemon and how chronyc is used for manual control.